OFFSET
1,2
COMMENTS
The even digits are 0, 2, 4, 6 and 8. This is not a permutation of the natural numbers as 101 and 103 cannot be part of the sequence, for instance.
EXAMPLE
a(1) = 1 jumps over 1 digit and lands on 4, an even digit;
a(2) = 2 jumps over 2 digits and lands on 6, an even digit;
a(5) = 6 jumps over 6 digits and lands on the 2 of 20, an even digit;
a(6) = 5 jumps over 5 digits and lands on the same even digit;
a(10) = 10: the 1 of 10 jumps over 1 digit and lands on the 2 of 20, an even digit;
a(10) = 10: the 0 of 10 jumps over 0 digit and lands on the same even digit; etc.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Eric Angelini and Giorgos Kalogeropoulos, Oct 29 2023
STATUS
approved